The production of alcohols from carbon monoxide and hydrogen has been previously described and a variety of different catalysts have been proposed.
For example, U.S. Pat. No. 2,061,470 describes the production of methanol from carbon monoxide and hydrogen using, as catalyst, the reduction product of a fused mixture of copper oxide and manganese oxide, or copper oxide and zinc oxide and an oxide of an element selected from chromium, vanadium, zirconium, aluminum, magnesium, titanium, thorium, silicon and cerium.
Further, U.S. Pat. No. 4,298,354 discloses a mixed metal oxide catalyst containing copper, thorium, an alkali metal and at least one other metal selected from Ca, Mo, Rh, Mn, Pt, Ce, Cr, Zn, Al, Ti, La, V, U, Ru, Re and Pd and its use for the production of methanol and alcohols containing from 2 to 6 carbon atoms.
European Patent Application No. 082 692 describes a mixed oxide catalyst composition containing copper and ruthenium, optionally a metal selected from Ce, Cr, Fe, Mn, Mo, Th and Zn and optionally an alkali metal or alkaline earth metal. The catalysts are described for the conversion of carbon monoxide and hydrogen to a product mixture containing carboxylic acids, hydrocarbons and alcohols. The products obtained from the use of this catalyst contain large amounts of carboxylic acids and hydrocarbons, the amounts of each of which in most cases exceed on a weight basis the amount of alcohols.
For an alcohol composition whose intended use is a motor fuel the presence of significant quantities of carboxylic acids is very undesirable. It is therefore an object of the present invention to provide a catalyst and a process in which it is used for the production of alcohols in which process significantly less acids are produced than is the case using the copper-ruthenium catalysts disclosed in the above mentioned European patent application.